http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Wancheol Myeong (검색결과 5 건)
- 무료
- 기관 내 무료
- 유료
-
Haemin Jeon,Wancheol Myeong,Jae-Uk Shin,Jong-Woong Park,Hyung-Jo Jung,Hyun Myung IEEE 2014 IEEE/ASME transactions on mechatronics Vol.19 No.5
<P>Structural displacement is considered an important indicator to assess structural conditions. To directly measure the displacement in the time domain, a visually servoed paired structured light system was proposed. The system is composed of two sides facing each other, each with one or two lasers that are controlled by a visually servoed two-DOF manipulator, a camera, and a screen. The relative six-DOF displacement between the two sides can be estimated by calculating the positions of the projected laser beams on the screens and the rotation angles of manipulators. To verify the performance of the proposed system, two kinds of field tests were carried out. A prototype of the system was built and installed on a steel frame building structure and a railway bridge, respectively. The estimated displacements were compared with the reconstructed displacement from an accelerometer. The test results verify the performance of the system and its applicability to real structures.</P>
-
Vision-based hybrid 6-DOF displacement estimation for precast concrete member assembly
Choi, Suyoung,Myeong, Wancheol,Jeong, Yonghun,Myung, Hyun Techno-Press 2017 Smart Structures and Systems, An International Jou Vol.20 No.4
Precast concrete (PC) members are currently being employed for general construction or partial replacement to reduce construction period. As assembly work in PC construction requires connecting PC members accurately, measuring the 6-DOF (degree of freedom) relative displacement is essential. Multiple planar markers and camera-based displacement measurement systems can monitor the 6-DOF relative displacement of PC members. Conventional methods, such as direct linear transformation (DLT) for homography estimation, which are applied to calculate the 6-DOF relative displacement between the camera and marker, have several major problems. One of the problems is that when the marker is partially hidden, the DLT method cannot be applied to calculate the 6-DOF relative displacement. In addition, when the images of markers are blurred, error increases with the DLT method which is employed for its estimation. To solve these problems, a hybrid method, which combines the advantages of the DLT and MCL (Monte Carlo localization) methods, is proposed. The method evaluates the 6-DOF relative displacement more accurately compared to when either the DLT or MCL is used alone. Each subsystem captures an image of a marker and extracts its subpixel coordinates, and then the data are transferred to a main system via a wireless communication network. In the main system, the data from each subsystem are used for 3D visualization. Thereafter, the real-time movements of the PC members are displayed on a tablet PC. To prove the feasibility, the hybrid method is compared with the DLT method and MCL in real experiments.
-
Sungwook Jung,Jae-Uk Shin,Wancheol Myeong,Hyun Myung 제어로봇시스템학회 2015 제어로봇시스템학회 국제학술대회 논문집 Vol.2015 No.10
Wind turbines need annual inspections to investigate their states which may have damages, such as cracks, erosion, bonding defects, cavities and delamination. Wind blades inspection, however, is a difficult process which needs specialized equipment and well-trained technicians to perform it manually. In addition, most approaches to inspect require pre-installed infrastructures like ropes or other platforms, so they are not appropriate for a close investigation and has a low preference. To overcome these problems, the need for a wall-climbing robot has emerged. In this paper, we suggest a MAV (Micro Aerial Vehicle) type wall-climbing robot that has four rotors to make thrust force for flying and four wheels for wall-climbing so that it can fly, stick, and move on a vertical and non-flat surface. The overall inspection process has two parts; macro and micro inspections. The main concept was verified throughout simulations.
-
Incremental Displacement Estimation (IDE) for Structural Health Monitoring Robot
Haemin Jeon,Jae-Uk Shin,Wancheol Myeong,Hyun Myung 제어로봇시스템학회 2012 제어로봇시스템학회 국제학술대회 논문집 Vol.2012 No.10
To measure 6-DOF displacement, a visually servoed paired structured light system (ViSP) has been introduced which is composed of two sides facing with each other, each with one or two lasers, a camera, a screen, and a 2-DOF manipulator. In the system, the lasers on both two sides project their parallel beams to the screen on the opposite side and 6-DOF relative displacement between two sides can be calculated using the positions of the three projected laser beams and the rotation angles of the manipulators. In the estimation process, extended Kalman filter (EKF) or Newton-Raphson method have been used. However, these aforementioned iterative methods have a drawback that the computation time is relatively long due to the multiple iterations. Therefore, in this paper, incremental displacement estimation (IDE) algorithm which updates the previously estimated displacement using the difference of the previous and the current observed data is introduced. To validate the performance of the newly proposed algorithm, various experimental tests have been performed. The results show that the ViSP with the IDE algorithm estimates the 6-DOF relative displacement between two sides with the same level of accuracy of EKF with multiple iterations in significantly reduced time.
-
실시간 구조물 변위 모니터링을 위한 증분형 변위 측정 알고리즘
전해민(Haemin Jeon),신재욱(Jae-Uk Shin),명완철(Wancheol Myeong),명현(Hyun Myung) 제어로봇시스템학회 2012 제어·로봇·시스템학회 논문지 Vol.18 No.6
The purpose of this paper is to suggest IDE (Incremental Displacement Estimation) algorithm for the previously proposed visually servoed paired structured light system. The system is composed of two sides facing with each other, each with one or two lasers with a 2-DOF manipulator, a camera, and a screen. The 6-DOF displacement between two sides can be estimated by calculating the positions of the projected laser beams and rotation angles of the manipulators. In the previous study, Newton-Raphson or EKF (Extended Kalman Filter) has been used as an estimation algorithm. Although the various experimental tests have validated the performance of the system and estimation algorithms, the computation time is relatively long since aforementioned algorithms are iterative methods. Therefore, in this paper, a non-iterative incremental displacement estimation algorithm which updates the previously estimated displacement with a difference of the previous and the current observed data is introduced. To verify the performance of the algorithm, experimental tests have been performed. The results show that the proposed non-iterative algorithm estimates the displacement with the same level of accuracy compared to the EKF with multiple iterations with significantly less computation time.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
